Structure such as a container or mobile shelter

ABSTRACT

A structure adapted to be loaded onto a vehicle provided with a hydraulic lifting arm type handling mechanism including two longitudinal bottom rails adapted to cooperate with guide rollers at the rear of the vehicle, and means for moving the rails between a deployed position, in which the rails cooperate with the guide rollers, and a retracted position, in which each rail is withdrawn into a housing in the bottom of the structure.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention concerns a structure, such as a container or a mobileshelter, designed to be loaded onto a vehicle provided with a hydrauliclifting arm type handling mechanism.

2. Description of the Prior Art

These structures are built around a framework whose lower part embodiestwo longitudinal rails which cross below cross-members and cooperatewith guide rollers at the rear of the vehicle chassis. Theselongitudinal rails are usually connected at the front part of thestructure, to uprights, between which a bail bar is provided at acertain height. The lifting arm of the handling mechanism (described forexample in French patent 2,109,109) is in the form of a telescopic boomarticulated to a subframe which is connected to the chassis of thevehicle. To load a structure the boom is activated and the arm is swungtowards the rear of the vehicle, a hook, carried by the free end of theboom engages the bail bar and the arm is then swung towards the front ofthe vehicle, during which maneuver the front of the structure is liftedand drawn towards the vehicle in an inclined position until its twobottom rails come into contact with the rollers mounted at the rear ofthe longitudinal rails of the vehicle. The structure's bottom rails thenroll on the rollers while the structure continues to move forward,returning to the horizontal position, whereupon the boom is extended. Atthe end of the maneuver the structure rests on the rollers and issupported at the front by the hook connected to the free end of thelifting arm, the horizontal part of which is accommodated between therails.

The configuration of the bottom of the structure (cross-members belowwhich the longitudinal rails project) sometimes causes problems,especially if the structure must travel on a roller or rollerball typeof the kind installed on aircraft. These types of handling decks canonly cooperate with a flat and continuous surface, which means that thestructure must be put on a pallet whose lower surface has thesecharacteristics.

SUMMARY OF THE INVENTION

The present invention is directed to reducing or even avoiding theseproblems.

To this end, the present invention proposes a structure such as acontainer or a mobile shelter adapted to be loaded onto a vehicleprovided with a hydraulic lifting arm type handling mechanism, thecontainer having two longitudinal bottom rails adapted to cooperate withguide rollers at the rear of the vehicle. According to the invention,the rails are rendered mobile between a deployed position in which theyare able to cooperate with the guide rollers and a retracted position inwhich each is withdrawn into a housing in the bottom of the structure.

By retracting the longitudinal rails, the main projections under thestructure are eliminated, which is particularly advantageous as thestructure can then rest on a larger area and consequently exert areduced pressure on the surface on which it rests, for example, on apallet with a flat and continuous bottom. Additionally, the height ofthe structure is reduced so that, for example, it can be made to complyto a template from which the rails project in the deployed position.

According to preferred features of the invention the structure has asubstantially plane undersurface from which the rails project when inthe deployed position. The rails and their respective housings areadapted so that in the retracted position a surface of each rail issubstantially coplanar with the undersurface of the structure andthereby closes the respective housing, and the structure then has asubstantially flat and continuous bottom.

Note that "substantially flat and continuous bottom means a surfaceadapted to cooperate with handling decks mounted onboard aircraft, andin particular a surface conforming to ISO standard 8323.

With the rails retracted it is, therefore, possible to roll thestructure directly over the handling decks and in particular rollerballtransfer plates. This represents a saving in weight because it is nolonger necessary to use a pallet with a flat and continuous bottom,avoiding the constraints associated with "packaging" the structure on apallet of this kind.

In a first preferred embodiment of the invention the structure hasmounting means for each rail enabling movement in translation in avertical plane in which the rail moves from the deployed position to theretracted position.

The means for rendering the rails mobile are thus provided in aparticularly simple, convenient and economical way.

In an alternative embodiment of the invention the structure has mountingmeans for each rail enabling movement in rotation about a longitudinalaxis about which the rail pivots from the deployed position to theretracted position.

As compared with retraction of the rails by movement in translationparallel to themselves, this solution has the advantage of requiring ahousing which in the floor of the structure occupies a space which isshallow in comparison with the height of the rail. Also, if theundersurface of the structure is required to be flat and continuous, itis advantageous not to close the housing by means of the lower surfaceof the rail because this surface may be deformed due to the heavy loadsto which it may be subjected, but instead by a lateral surface which ismuch less likely to be deformed.

According to other advantageous features of the invention, two removableor retractable rollers for facilitating loading and unloading of thestructure on stabilized ground or its transfer to a trailer or a dockare provided at the rear of the structure. At the front of thestructure, two removable or retractable shoes are provided, each ofwhich is adapted to cooperate with a longitudinal rail of the chassis ofthe vehicle which carries the structure to improve locking of thestructure in place, in particular with regard to transverse forces.

The explanation of the invention will now continue with the descriptionof a mobile technical shelter in accordance with the invention givenhereinafter by was of non-limiting illustrative example with referenceto the appended drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic perspective view of the shelter;

FIGS. 2 through 6 are schematic views in longitudinal cross-sectionshowing the unloading of the shelter from a truck, which has a hydrauliclifting arm type handling mechanism and the reconstitution of a flat andcontinuous surface on the bottom of the shelter;

FIG. 7 is a schematic view, in elevation, showing the loading of theshelter into an aircraft;

FIG. 8 is a partial view of the cross-section taken on the lineVIII--VIII in FIG. 2, the left and right half-sections respectivelyshowing the cooperation of the rails of the shelter with two differenttypes of guide rollers that are currently used;

FIG. 9 is a simplified partial bottom view of the shelter from FIG. 1;

FIG. 10 is a partial view in cross-section taken on the line X--X inFIG. 9 or the line X--X in FIG. 12;

FIG. 11 is a view similar to FIG. 10 with the rail retracted;

FIG. 12 is a partial view in cross-section taken on the line XII--XII inFIG. 10;

FIG. 13 is a top view of an assembly, integrated into the shelter ofFIG. 1, combining the rails, their housings and the means whereby therails are movable between the deployed position and the retractedposition;

FIG. 14 is an enlarged view of the top right-hand corner FIG. 13;

FIG. 15 is a partial view in cross-section taken on the line XV--XV inFIG. 9;

FIG. 16 is a similar view to FIG. 15, with the rail retracted;

FIGS. 16A and 16B show, in a similar manner to FIGS. 10 and 12, avariant of the shelter which differs, in particular, in the means forpivoting the rails, FIG. 16A being a cross-section taken on the lineA--A in FIG. 16B which is a cross-section taken on the line B--B in FIG.16A.

FIGS. 16C and 16D similarly show another variant with yet other meansfor pivoting the rails, FIG. 16C being a cross-section taken on the lineC--C in FIG. 16D which is a cross-section on the line D--D in FIG. 16C.

FIGS. 17 and 18 show another variant of the mechanism for moving therails;

FIG. 19 is a partial front view of the shelter from FIG. 1 showing oneof its shoes;

FIG. 20 is a partial view in cross-section taken on the line XX--XX inFIG. 19 showing the shoe in both the retracted and extended positions;

FIG. 21 is a view similar to FIG. 20 but showing the shoe only in theextended position;

FIG. 21A shows, in a view similar to FIG. 19, a different type of shoefastened to a first type of vehicle longitudinal rail;

FIG. 21B shows the shoe locked to a second type of longitudinal rail;

FIG. 21C is a plan view detailing the mounting of the shoe to theshelter;

FIGS. 22 and 23 are, respectively, partial bottom and rear views of theshelter from FIG. 1, and show a retractable roller fitted at the rearend of the shelter;

FIGS. 24 and 25 are partial views in cross-section respectively taken onthe line XXIV--XXIV in FIG. 25 and on the line XXV--XXV in FIG. 24,showing the cooperation of the shelter and struts shown in FIGS. 4through 6; and

FIGS. 26 and 27 are views similar to FIGS. 24 and 25 showing a variantembodiment and positioning of the struts.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

A mobile technical shelter 1, shown in FIG. 1, is an ISO standardparallelepiped-shape box and has ISO corner fittings 2. In each of thethree outside surfaces of each corner fitting 2 is formed an elongateopening (see FIGS. 24 through 27). The mobile shelter 1 has a frontsurface 3 incorporating a recess 4 in which is disposed a bail bar 5.The mobile shelter 1 has an undersurface 6 forming a flat bottom whichis substantially coplanar with both the bases of each of the bottomcorner fittings 2 and with the bottoms of longitudinal rails 7A and 7B.The mobile shelter also has a mechanism (not visible in FIG. 1) formoving the rails 7A and 7B between a deployed or extended position, inwhich the rails project outward relative to the undersurface 6 (positionshown in FIG. 1), and a retracted position in which each rail ispositioned in a housing in the bottom of the structure (not shown inFIG. 1). The rails and their respective housings are adapted so that inthe retracted position a surface of each rail is substantially coplanarwith the undersurface 6 and, therefore, closes the housing so that theshelter has a substantially flat and continuous bottom. Two removablerollers 8A and 8B are additionally provided at the rear end of theshelter's undersurface 6 and at the front two retractable U-shaped shoes9A and 9B are mounted in line with-the rails 7A and 7B.

FIG. 2 shows the shelter loaded onto a truck 10 whose chassis embodiestwo longitudinal rails 11 each disposed on one side of a median axis.Mounted on the median axis is a well known type of handling mechanismincorporating a hydraulic lifting arm. As can be seen more clearly inFIGS. 3 through 5, this mechanism includes one or more rollers 12 at therear end of each longitudinal rail, a subframe 13 mounted transverselyto the longitudinal rails, a telescopic boom 14 articulated transverselyto the subframe and a pair of hydraulic rams 15 each of which istransversely pivoted at respective ends to one of the longitudinal rails11 and to the boom 14.

In the transport position (FIG. 2), the rails 7A and 7B rest on therollers 12 and the shelter I is supported at the front by a hook 16 atthe end of the boom 14 which engages the bail bar 5. The subframe 13located between the two longitudinal rails 11 of the truck 10 isprovided on each side with well-known hooks 90A and 90B (see FIG. 8)whose open sides are oriented transversely and towards the rear andreceive a finger 17A and 17B, respectively, attached to the respectiverails 7A or 7B (see FIG. 8). The hooks and fingers 17A and 17B make itpossible to position the center of gravity of the shelter I at apredetermined position relative to the truck 10 and to maintain thisposition, especially when strong braking forces are applied. Eachlongitudinal rail 11 is capped by a U-shaped part of one of the shoe, 9Aand 9B so as to secure the shelter 1 to the truck 10, especially whenstrong lateral forces are exerted, as in turns, for example.

When the shelter 1 is to be unloaded from the truck 10, the shoes 9A and9B are raised and a piston rod of a ram 91 of the boom 14 is withdrawnto retract the boom and to slide the structure 1 towards the rear of thetruck 10. During this movement the fingers 17A and 17B are disengagedfrom the hooks 90A and 90B, after which the piston rods of the rams 15are deployed to tilt the lifting arm of the boom 14. The sheltercontinues to roll backwards on the rollers 12, tilting as it does sountil the rollers 8A and 8B come into contact with the ground (see FIGS.3). The shelter continues to roll on the ground in a tilted positionuntil the boom reaches an abutment on the subframe 13. The subframe 13then turns about a pivot axis returning the shelter, which by this timehas been moved sufficiently clear of the truck 10, to a horizontalposition on the ground. When the shelter 1 is resting entirely on theground (FIG. 4) the hook 16 is disengaged from the bail bar 5 and thetruck moves forward slightly and can then drive off after the handlingmechanism is returned to its original position (FIG. 5).

The movement of the handling mechanism is stopped between the positionsshown in FIGS. 3 and 4 while struts or feet 18 (described later withreference to FIGS. 24 and 25) are installed into the bottom cornerfittings 2 at the front end of the shelter; the feet 18 come intocontact with the ground and prevent the rails 7A and 7B from resting onthe ground.

As can be seen in FIG. 5, after the shelter 1 has been placed on theground two additional feet 18 are installed in the bottom cornerfittings at the rear end of the shelter 1 and are operable to raise theshelter 1 so that it rests only on the feet 18. It is then possible toremove the rear rollers 8A and 8B and to retract the rails 7A and 7B tomake the bottom of the shelter flat and continuous (FIG. 6), withoutsharp projections, protuberances or significant recesses, so that it cantravel over a rollerball transfer plate without damaging the transferplate. The rollerballs on the transfer plate usually have a diameter of25.4 mm (one inch), and the distance between them is usually 127 mm(five inches).

It is then possible to remove the feet 18 and to load the shelter 1 byconventional means onto a roller system elevator 19 to enable theshelter to be loaded into an aircraft 20 whose floor is fitted with arollerball type transfer plate enabling the shelter to be moved in anydirection while in the aircraft 20 via the tops of the rollerballs.

Note that it is possible to rest the shelter I on the ground on therails 7A and 7B; that is to say to mount the front feet 18 only afterthe shelter 1 is put on the ground, but it is more beneficial to preventcontact between the rails 7A and 7B and the ground, as this prevents therails 7A and 7B from being soiled which could impede their retraction byclogging the housings.

More generally, note that the rails 7A and 7B can be retracted duringthe unloading process, in which case the front feet 18 are fitted beforethe shelter 1 is set on the ground and that the shoes 9A and 9B can beleft in place until this time and then removed.

Of course, the same operations are carried out in the reverse order tounload the shelter 1 from an aircraft and load it onto a truck.

Given that the loading operation is usually begun with the structure andthe vehicle, on which the structure is to be loaded, off-center andmisaligned, the rollers 12 at the rear of the handling mechanism mustperform a centering function in addition to a rolling function. Thiscentering function is obtained by use of an inclined surface provided onthe exterior sides of the rails. In practice a first type of roller (seeleft-hand half-section in FIG. 8) is in the form of a horizontal axis"disbolo" 22 providing the rolling and centering functions; in a secondtype of roller (see right-hand half-section in FIG. 8) a horizontal axisroller 23 is used with a cylindrical surface on the inside and a conicalsurface on the outside.

The shelter schematically shown in FIGS. 1 through 7 will now bedescribed in more detail.

Note that the rails 7A and 7B are very different from the longitudinalrails of conventional structures because they do not constitute any partof the framework of the shelter and because their length is much lessthan that of the shelter (one third of the latter in this example).

The framework of the lower part of the shelter 1 (see FIG. 9) has oneach side an outer longitudinal rail 24 of relatively largecross-sectional area. Attached to the outer longitudinal rail 24 is aninner longitudinal rail 25 of relatively smaller cross-section area. Twoplates 26 are disposed between the inner longitudinal rails 25, and arewelded to them and to the remainder of the shelter framework (notvisible in FIG. 9). The bottom surfaces of both the outer and innerlongitudinal rails 24 and 25 and the plates 26 are flush. A hollowrectangular space for the rails 7A and 7B is delimited by the innerlongitudinal rails 25 and by the crossmembers 27 which are similar incross-section to the longitudinal rails 24. Outside the crossmembers 27are crossmembers 28 which are similar to the inner longitudinal rails25. The lower surfaces of the crossmembers 27 and 28 are flush with thelower surfaces of the longitudinal rails 24 and 25 and the plates 26.

An assembly 29, seen in plan view in FIG. 13, is disposed in the hollowrectangular space defined above. The assembly 29 is welded at its edgesto the frame formed by the crossmembers 27 and 28 and the longitudinalrails 25 and 27. The assembly 29 embodies the rails 7A and 7B, theirhousings and the means which the rails 7A and 7B are moved between thedeployed and retracted positions. The assembly 29 has two U-shapedlongitudinal sections 30A and 30B whose interiors, respectively, formthe housings for the rails 7A and 7B; two U-shaped end sections 31A and31B accommodating the means for operating and locking the rails 7A and7B; and three bottom plates 32A, 32B and 32C the same length as theassembly 29 and to which the sections 30A, 30B, 31A and 31B are welded.The bottom surfaces of the plates 32A, 32B and 32C are flush with theremainder of the bottom of the shelter 1 which forms a flat andcontinuous surface except for openings 33A and 33B in the assembly 29.

A shaft 34 is carried at each end and at the center of each U-shapedlongitudinal section 30A and 30B by pairs of vertical lugs 35 which arewelded to a horizontal portion of the U-shaped longitudinal sections 30Aand 30B. The shafts 34 of each section 30A and 30B are each alignedalong a respective parallel longitudinal (geometrical) axis about whichthe rails 7A and 7B rotate from the deployed position (FIGS. 9, 10, 12and 15) to the retracted position (FIGS. 11 and 16).

Each rail 7A and 7B is generally L-shaped with the wider flange formedby a plate 37 and the narrower flange formed by two plates 38 and 39. Arelatively smaller L-shaped section 40 joins the plates 38 and 39 withthe plate 37 except at the location of lugs 36 where a shorter L-shapedsection 41 is used. U-shaped abutments 42 are welded to the upper partsof the U-shaped longitudinal sections 30A and 30B. This provides a meansfor correctly locating the rails 7A and 7B in the retracted position bycoming into contact with the L-shaped section 40 and 41 (see FIGS. 11and 16) of the rails 7A and 7B. Note that in the retracted position theplates 37 completely close the openings 33A and 33B completely, and inthis position are continuous with the plates 32A, 32B and 32C. A bevelor a rounded surface is provided at the facing edges of the plates toavoid any sharp edge likely to damage a rollerball transfer plate overwhich the shelter travels.

At each end of the assembly 29 the shafts 34 are also carried by pairsof vertical plates 43A and 43B which are welded to the plates 32A (rail7A) and 32B (rail 7B). The outer plate 43A extends away from the shaft34 and has a ring 44 welded to the end section 31A and 31B, and a shaft45 parallel to the shaft 34 is disposed in the ring 44. A plate 46 iswelded over the plate 43B and part of the plate 43A facing it so that asquare or rectangular cross-section passage is delimited by the plate32A or 32B, the plates 43A and 43B and the plate 46. Inside this passageis a is shoe 47 in the form of a nut whose cross-section matches that ofthe passage. A bracket 49 for rotatably mounting and axially retaining ascrew 50 is welded to an outer end of the passage opposite the shaft 34.A lever 51 mounted on the shaft 45 is connected by a cable 52 to one ofthe lugs 36, a short tube 53 is welded to the lever 51 and is adapted toreceive a rod (not shown) which is used to turn the lever 51.

To retract or deploy the rails 7A and 7B the lever 51 and theprism-shaped end 54 of the screw 50 are accessed via an opening 55(FIGS. 13 and 14) provided in the top of the U-shaped sections 31A and31B by an operator inside the shelter 1. Each rail is retracted byapplying a wrench to the end 54 of each screw 50 to turn it to retractthe shoe 47. When the two shoes are retracted a rod is inserted into thetube 53 to turn the lever 51, the cable 52 then pulling on the rails topivot them towards the retracted position, after which the screws 50 areturned in the opposite direction until the shoes 47 bear hard againstthe lugs 36 to lock the rails into the retracted position (FIG. 11). Todeploy the rails the levers 51 are turned which loosens the cables 52.The screws 50 are turned to retract the shoes 47 sufficiently. The railsare then deployed under their own weight and the screws 50 are turned inthe opposite direction until the shoes 47 bear hard against the plate 37to lock the rail in the deployed position (FIG. 10).

As seen in FIGS. 13, 15 and 16, the assembly 29 also includes threeU-shaped sections 56 disposed transversely in the middle of the assemblyto provide strength. The strengthening sections are welded to the plates32A, 32B and 32C and to the U-shaped longitudinal sections 30A and 30B.At the positions of the fingers 17A and 17B the top of each U-shapedlongitudinal section 30A and 30B is formed with openings 57A and 57Bthrough which the fingers 17A and 17B, respectively, pass when the railis in the retracted position (see FIG. 16). Note that when deploying therails if they do not drop spontaneously the operation can be assisted byappropriate action on the end of the fingers projecting above theopenings 57A and 57B.

In a variant of the invention shown in FIGS. 16A and 16B, the lever 51and the shaft 45 are replaced with a screwthreaded tube 100 welded tothe plate 43A and a screw 101 which cooperates with the tube 100 andwith the cable 52. In this variant, the maneuver to retract or deploythe rails is similar to before, except that the screw 101 is turnedinstead of the lever 51 being activated. Extender tubes 102 and 103 areprovided for turning the screws 50 and 101. They are engaged,respectively, over the prism-shaped end 54 of the screw 50 and over aprism-shaped end 104 of the screw 101. The other end of each extensiontube 102 and 103 is accessible by an operator on the outside of theshelter. Note that the opening 55, which is no longer of any utility, iseliminated and that the fingers 17A and 17B and the lugs 35 are boltedinstead of welded.

The variant shown in FIGS. 16C and 16D is similar to that which has justbeen described with reference to FIGS. 16A and 16B but there is nolonger any cable 52. Instead, a prism-shaped head 105 is provided on theshaft 34, an extension tube 106 being engaged over the head andextending to one side of the shelter. Note that in this variant the railcan swing to the deployed position not only under its own weight butalso because of a torque transmitted by the tube 106.

In other variants (not shown) in which the lever 51 is eliminated, theoperator acts directly by pulling on the two cables 52 which can bereplaced by a single cable or strap at the middle of the rail.

There will now be described with reference to FIGS. 17 and 18 a variantof the means for moving the rails between the deployed and retractedposition in which the rails 207A and 207B translate in a vertical planefrom the deployed position (FIG. 17) to the retracted position (FIG.18).

Each rail 207A and 207B is mounted in a slideway 210 which is integratedinto the bottom of the shelter 1. To be more precise,.the slideway 210acts as a rail housing. An opening 211 is provided at the top of theslideway 210 for inserting a round shank (not shown) of a jack typelifting rail (also not shown). The end of the round shank has an oval istransverse finger which is inserted into an opening (not shown) ofsimilar cross section in the rail 207A and 207B so that the shank islocked to the rail after it is turned through about a quarter-turn. Thelifting rail is used to raise the rail from inside the structure.

A shoe 212 is provided to immobilize and guide the rail and is movabletransversely to the rail 207A and 207B by a drive mechanism of the sametype as that for the shoe 47 (see FIGS. 10 and 11). The shoe bearsagainst the rail to lock it into each of the deployed and retractedpositions. The rails 207A and 207B each have an opening 213 into whichthe shoe 212 is inserted when the rails are in the deployed position(FIG. 17); and a groove 214 in which the end of the shoe 212 slides wheneach rail moves. Each end of each groove 214 forms an abutment for theshoe, one in the deployed position and one in the retracted position.

Adjustable abutments (not shown) are used to provide for more accuratepositioning of the rails 207A and 207B in the retracted position.

Of course, depending on circumstances, it is totally feasible to providedifferent means for integrating the rails and for rendering them mobilerelative to a structure like the shelter 1. In particular, provisionsmay be made for the movement of the rails to be motorized rather thanmanual and to be synchronized rather than independent.

As can be seen in FIG. 19, each front shoe 9B (or 9A not shown) has aU-shaped bottom part designed to engage the longitudinal rail 11 by itsupper and inside surfaces or a longitudinal rail 58 of a trailer ontowhich the shelter or the structure is loaded by its upper and outsidesurfaces.

Each of the shoes 9A and 9B is formed by a plate 59 which at one end hastwo lugs 60 fastened to a shaft 61 supported by vertical bearings 61Awelded above a front bottom cross-member 62 of the shelter 1. TheU-shaped part of the shoe is fastened to an internally screwthreadedsleeve 63 and guided between vertical plates 64 which are welded to theplate 59. A plate 65 is fastened to the plates 59 and 64 and has athreaded hole in its central part. Screwthreaded ends of a rod 67cooperate with the screwthreads of the sleeve 63 and the plate 65 whichare right-hand and left-hand threads, respectively, so that turning therod 67 causes the sleeve 63 to slide in the plates 64 so that theU-shaped portion of the shoe 9A or 9B bears against the longitudinalrail (11, for example) of the vehicle 10 and the plate 65 bears againstthe cross-member 62, thus, locking the shoe 9A or 9B in position (FIG.21).

Above the shoe is an extension of the recess 4 in which the shoe 9A or9B is housed when in the retracted position (Bee FIG. 20). Holes 68 and69 are provided in one of the lugs 60 and one of the vertical bearings61A, respectively, and are aligned with each other when the shoe is inthe raised position. A pin is then inserted in the holes 68 and 69thereby locking the shoe 9A and 9B in the retracted position.

In the embodiment shown in FIGS. 21A, 21B and 21C the U-shaped part ofthe shoes 9A and 9B is replaced with a holding assembly 110 which isremovable rather than permanently fixed, and has a recess to accommodatethe shoe in the raised position. In this example, the front surface ofthe shelter includes, at the bottom on each side, a series of three,side-by-side parallelepiped-shaped recesses 111A, 111B and 111C and ashaft 112 which is fixed into the middle recess 111B. The holdingassembly 110 includes a plate 113 which is fixed by means of therecesses 111A, 111B and 111C and the shaft 12; a vertical rod 114, whichcooperates, via a screwthread, with the plate 113; a baseplate 115,pivoted to the lower end of the rod 114; a screw 116 which cooperateswith the baseplate 115; and an angle-bracket 117 which turns about theend of the screw 116.

The plate 113 has two circular fixing pins 118A and 118B, the outsidediameter of which matches the height of the recesses 111A and 111C, thedistance between which matches the distance between the fixing pins 118Aand 118B also matches the distance between the recesses 111A and 111C sothat the only degree of freedom remaining when the pins 118A and 118Bare respectively inserted in the recesses 111A and 111C is movement intranslation along the length pin axis. To complete the locking to theshelter in this variant, the plate 113 also includes a hook 119 which isengaged on the shaft 112 and locked by tightening a nut 120 at the endopposite the curved end (see FIG. 21C in particular). To cooperate withthe rod 115 the plate 113 includes two screwthreaded bores 121A and121B, either of which may be used, as appropriate.

The rod 114 has a prism-shaped head 122 for turning it, a screwthreadedpart 123 which cooperates with either of the bores 121A or 121B, and, atthe opposite end, a pivotable mount provided with a smooth hole for thebaseplate 115. A nut 124 for the screw 116 is welded on coaxially withthe smooth hole of the rod 114.

When the shelter is transported on a vehicle with longitudinal rails 11(FIG. 21A), the rod 114 is inserted in a bore 121A, the baseplate 115 isarranged with the screw 116 on the inside, and the upper end of theangle-bracket 117 is applied against the lower surface of the horizontalpart of the longitudinal rail 11.

When the shelter is transported on a vehicle with longitudinal rails 58,in particular a trailer (see FIG. 21B), the rod 114 is inserted in thebore 121B, the baseplate 115 is arranged with the screw 116 on theoutside, and the end of the horizontal part of the angle-bracket 117bears on the bottom of the longitudinal rail 58.

Note that the screw 116 of each holding assembly 110 locks the shelterlaterally and that the clamping of the longitudinal rail between thebaseplate 115 and the angle-bracket 117 secures it vertically.

This vertical attachment is advantageous because it prevents impactsduring transportation which could be sufficiently intense to deform thebottom of the shelter, compromising its ability to roll directly on anaircraft type rollerball floor.

Finally, note that the longitudinal rail securing device just describedwith reference to FIGS. 21A, 21B and 21C can be used on structures ofdifferent types and, in particular, without rails which are movablebetween a deployed position and a retracted position.

The removable rear roller 8B and the means for mounting it will now bedescribed with reference to FIGS. 22 and 23. The roller 8A is analogous.

The roller is mounted to rotate on vertical lugs 70 which are attachedwith reinforcing ribs to a horizontal flat fork 71 which carries twovertical flanges 72 and 73 respectively screwed to the rear and sidesurfaces of the shelter 1 at the bottom and beyond the corner fitting 2which is left exposed. This position has the advantage that the cornerfitting 2 is still available, in particular for installing the feet 18.

FIGS. 24 and 25 show one example of a foot 18 that can be installed inthe corner fitting 2 by means of a conventional system of elongate cams74 and 75, which are turned 90 relative to each other, and lock the foot18 to the corner fitting 2. The foot 18 is essentially a jack with acircular pad 77 which is mounted at the end of a rod 78 of ademultiplier mechanism 79. The demultiplier mechanism 79 is operatedwith a crank-handle which turns about an axis 80.

In a variant of the foot 18 shown in FIGS. 26 and 27, the demultipliermechanism 179 is permanently installed over the corner fitting 2 in arecess provided for this purpose and the rod 178 passes through openingsin the corner fitting 2. The pad 177 as simply inserted into the end ofthe rod 178 which can be raised sufficiently to expose the bottomopening and the interior of the corner fitting 2.

Preferably, provisions are made inside the shelter for stowing the rearrollers 8A and 8B and the feet 18 regardless of which variant of feet 18is used.

Naturally, depending on circumstances, removable rather than retractablefront shoes or retractable rather than removable rollers may beutilized. For example, the rollers described in French Patent 2,358,352may be used and provided with covers for closing the openings of theroller housing.

Furthermore, note that the features of the invention may be implementedin structures designed to be loaded onto a vehicle provided with alifting arm type handling mechanism which are different from the shelter1, such as containers, standard IATA and ATA pallets and mobile packingcases.

More generally, the invention is not limited to the examples describedand shown, but to the contrary encompasses all variants that may suggestthemselves to a person skilled in the art.

What is claimed is:
 1. A structure adapted to be loaded onto a vehiclehaving a hydraulic lifting-arm-type handling mechanism, said structurecomprising:a bottom member having a bottom surface; a handling barpositioned with respect to said bottom member; at least one bottom railjuxtaposed said bottom member of said structure; a housing connected tosaid bottom member of said structure, said housing having an open sidecontiguous with said bottom member, said housing being adapted toreceive said at least one bottom rail; and means for moving said atleast one bottom rail between a first position whereby said at least onebottom rail extends in a direction away from said bottom surface of saidbottom member and a second position whereby said at least one bottomrail forms a substantially planar surface with said bottom surface ofsaid bottom member, said moving means being connected to said at leastone bottom rail.
 2. A structure according to claim 1 wherein said atleast one bottom rail of said structure has a first planar surface; andsaid housing is adapted so that when said at least one bottom rail is insaid second position said first planar surface of said at least onebottom rail is coplanar with said bottom surface of said bottom memberof said structure and said at least one bottom rail closes said openside of said housing.
 3. A structure according to claim 2 furthercomprising means for mounting said at least one bottom rail to saidstructure, said mounting means being attached to said structure.
 4. Astructure according to claim 2 wherein said housing is a slidewayadapted to receive said at least one bottom rail; and said structurefurther comprises means for locking said at least one bottom rail inposition, said locking means being connected to said structure.
 5. Astructure according to claim 4 wherein said at least one bottom rail hasa groove therein, said groove having a first end and an opposite end;said at least one bottom rail having a bore therein located at saidfirst end of said groove; said slideway having a first wall, said firstwall of said slideway having a hole therein aligned with said groove insaid at least one bottom rail; and said means for locking said at leastone bottom rail in position comprises:a shoe disposed in said hole ofsaid first wall of said slideway, said shoe having a first end and anopposite end, said first end of said shoe being located in said grooveof said at least one bottom rail.
 6. A structure according to claim 3wherein said at least one bottom rail has a longitudinal axis, saidmeans for mounting said at least one bottom rail to said structure beingconnected to said at least one bottom rail, and said means for movingsaid at least one bottom rail comprises:means for rotating said at leastone bottom rail connected to said at least one bottom rail, saidrotating means being operable for rotating said at least one bottom railbetween said first position and said second position; and said structurefurther comprises means for locking said at least one bottom rail inposition, said locking means being connected to said structure.
 7. Astructure according to claim 6 wherein said locking means comprises:ashoe having a first end and an opposite end, said first end of said shoebeing juxtaposed said at least one bottom rail; a drive mechanismattached to said opposite end of said shoe, said drive mechanism beingadapted to move said first end of said shoe linearly into contact withsaid at least one bottom rail; and a screw member attached to said drivemechanism, said screw member being adapted to communicate with saidshoe.
 8. A structure according to claim 6 wherein said rotating meanscomprises:a lever having a first end and a second end, said second endof said lever being fixed relative to said at least one bottom rail; acable having a first end connected to said first end of said lever and asecond end connected to said at least one bottom rail; and means foroperating said lever.
 9. A structure according to claim 6 wherein saidrotating means further comprises:a screw-threaded tube being fixedrelative to said at least one bottom rail; a screw located in saidscrew-threaded tube, said screw having a first end and a second end; anda cable having a first end and a second end, said first end of saidscrew being connected to said first end of said cable, said second endof said cable being connected to said at least one bottom rail at apoint about said longitudinal axis of said at least one bottom rail. 10.A structure according to claim 7 wherein said rotating means furthercomprises:a pivot shaft having a prism-shaped head, said pivot shaftbeing connected to said at least one bottom rail and adapted forrotating said at least one bottom rail about said pivot shaft, saidpivot shaft constituting said longitudinal axis of said at least onebottom rail, said pivot shaft being connected to said housing of saidstructure; head extension means connected to said prism-shaped head ofsaid pivot shaft and extending in a direction substantially the same assaid longitudinal axis of said at least one bottom rail, said headextension means being adapted to rotate said pivot shaft; and screwextension means connected to said screw and extending in a directionaway from said shoe, said screw extension means being adapted to operatesaid shoe between a first position in which said at least one bottomrail is unlocked and a second position in which said at least one bottomrail is locked in position.
 11. A structure according to claim 10wherein said at least one bottom rail is shorter than said structure.12. A structure according to claim 5 wherein said at least one bottomrail is shorter than said structure.
 13. A structure according to claim3 wherein said vehicle has a sub-frame assembly, said vehicle comprisinga hook connected to said sub-frame assembly of said vehicle; and whereinsaid at least one bottom rail comprises a transverse locking fingeradapted to cooperate with said hook on said sub-frame assembly of saidvehicle.
 14. A structure according to claim 6 further comprising:aroller assembly removably attached to said structure, said rollerassembly being positioned to extend a predetermined distance from saidbottom surface of said bottom member of said structure.
 15. A structureaccording to claim 14 wherein said roller assembly further comprisesmeans for retracting said roller assembly to a position within saidstructure.
 16. A structure according to claim 6 further comprising:a padassembly removable attached to said structure, and wherein said rollerassembly is positioned to extend a predetermined distance from saidbottom surface of said bottom member of said structure.
 17. A structureaccording to claim 16 wherein said pad assembly comprises means forretracting said pad assembly to a position within said structure.